Moon & Mars Orbiting Spinning Tether Transport - Tethers Unlimited

"JupiterandBeyond"Tether cut CUT:< + 1 km/s ∆vPlutoProbeORBITALMOTIONDual Probefrom InnerSolar System.Figure 7. Hyperbolic Dual Payload Tether Concept: Jupiter and Beyond.CONCLUSIONSWe have shown that two ideal rigid tethers rotating tethers in highly elliptical orbits about Earthand Mars can provide rapid interplanetary transport from a suborbital trajectory above the Earth'satmosphere to a suborbital trajectory above the Martian atmosphere and back. Real tether materialshave both elasticity and damping. The Hoytether structure then adds its own damping and anon-linear elasticity and strength response as the secondary strands come into play after sufficientelongation. Then, depending upon the placement of intermediate masses along the tether, the longtether structure would have libration, pendulum, and skip-rope modes, plus longitudinal,transverse, and torsional vibrational modes. Additional analysis is needed to study the excitationof those modes, ways to minimize the excitation, and how the existence of high amplitudeoscillations of those modes could affect the accuracy of the catch-and-throw operations.Synergistic use of a rotating tether between parts of a payload for artificial gravity for additionalvelocity increments in encounters with other planets looks potentially attractive but needs furtherstudy. Use of reels and grappling fixtures already developed for MERITT would reduce thetechnological risk.ACKNOWLEDGMENTSThis research has been supported in part by Contract 07600-011 from the NASA Institute forAdvanced Concepts, Dr. Robert A. Cassanova, Director; and in part by the Tethers Unlimited, Inc.IR&D program.14